Tag: pressure in liquids and gases

Quizzes (11) Questions (110)

Questions Related to pressure in liquids and gases

Multiple choice physics pressure in liquids and gases pressure dependence on force and area concept of pressure pressure on surface

As the depth of a liquid increases, the pressure of liquid decreases.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 pressure at a point in a fluid is = $\rho gh $ where $\rho$ is the density of the liquid , h is the height or depth of the object from the surface , so pressure increases with increase in depth so given statement is false .

hence option (B) is correct .

Multiple choice physics pressure in liquids and gases pressure dependence on force and area concept of pressure pressure on surface

The area of cross-section of the pump plunger and the press plunger of hydraulic press are $0.03 m^2$ and $9 m^2$ respectively. How much is the force acting on the pump plunger of the hydraulic press overcomes a load of 900 kgf?

  1. <span>2 kgf</span>

  2. <span>3 kgf</span>

  3. <span>4 kgf</span>

  4. <span>5 kgf</span>
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$Load=900 kgf, Effort (E)=?$
Area of cross section of the press plunger $=a _1=9 m^2$
Area of cross - section of the pump plunger $=a _2=0.03 m^2$
By Pascal's law,
Pressure exerted by pump plunger $=$ pressure exerted on press plunger.
i.e., $\displaystyle \frac {L}{E}=\frac {a _1}{a _2}\Rightarrow \frac {900 kgf}{E}=\frac {9 m^2}{0.03 m^2}$
$\displaystyle \Rightarrow E=\frac {900 kgf\times 0.03 m^2}{9 m^2}=3 kgf$.

Multiple choice physics pressure in liquids and gases pressure dependence on force and area concept of pressure pressure on surface

Force exerted by a truck is 500000 N and the pressure on the ground is 2500000 Pa. Calculate the area of contact of tyres with ground?

  1. <span>$0.1m^2$</span>

  2. <span>$0.2m^2$</span>

  3. <span>$0.3m^2$</span>

  4. <span>$0.4m^2$</span>
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Force $(F)=500000 N$
$Pressure=250000 Pa, Area (A)=?$
$A=\frac {F}{P}=\frac {500000}{2500000}m^2=0.2m^2$.

Multiple choice physics pressure in liquids and gases pressure dependence on force and area concept of pressure pressure on surface

Pressure is vector quantity .State true or false.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Pressure is a scalar quantity, not a vector quantity. It has a magnitude but no direction associated with it. Pressure acts in all directions at a point inside a gas. At the surface of a gas, the pressure force acts perpendicular to the surface.

For example. one that does not appear to move or flow. While the gas as a whole does not appear to move, the individual molecules of the gas, which we cannot see, are in constant random motion. Because we are dealing with a nearly infinite number of molecules and because the motion of the individual molecules is random in every direction, we do not detect any motion. If we enclose the gas within a container, we detect a pressure in the gas from the molecules colliding with the walls of our container. We can put the walls of our container anywhere inside the gas, and the force per area (the pressure) is the same. We can shrink the size of our "container" down to an infinitely small point, and the pressure has a single value at that point.

Therefore, it is false. 

Multiple choice physics pressure in liquids and gases pressure dependence on force and area concept of pressure pressure on surface

Two stretched remembrance of area $2$ and $3\ m^{2}$ are placed in a liquid at the same depth. The ratio of the pressure on them is

  1. $1:1$

  2. $2:3$

  3. $\sqrt {2}:\sqrt {3}$

  4. $2^{2}:3^{2}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Hydrostatic pressure at a given depth depends only on the density of the liquid, gravity, and the depth (P = rho*g*h). It is independent of the surface area of the object.